It’s about a weird or crazy girl which is pursued because she knows a certain code or combination for some sort of safe or a grave number and then she writes the code on a piece of glass covered in sand but in the end it turns out that she wrote the code backwards and the real one can only be seen in a mirror.
Could it be Don’t Say a Word (2001)?
Thank you 🙂
You’re Welcome, glad I could help 🙂
Definitely sounds like “‘don’t say a word” to me…
Solved
Great, thanks RobinS!